This invention relates to an ice maker, and in particular to a control circuit for an auger type ice maker.
Such a control circuit that has been used heretofore is one as disclosed in the specification of the U.S. Pat. No. 3,365,901. According to this Patent, an ice making cycle is initiated upon the closure of an ice level detection switch which causes an auger motor which is also called a gear motor to start to operate and causes a thermally operated time delay switch to be energized. In a predetermined time delay due to the time delay switch, an ice maker compressor motor is energized. At the end of the ice making cycle, when the ice level detecting switch is operated to open, the ice maker compressor as well as the time delay switch are immediately deenergized while the auger motor continues to be run until the time delay switch returns to its cool position.
In this patent a stirring rod is provided which serves to prevent the possibilities of freeze-up in the ice storage hopper and to dispense a quantity of ice. Since this stirring rod is still rotating even though the ice storage hopper is filled with ice, the ice level switch may be re-opened, since the upper configuration of the ice stored within the hopper changes from convex and concave during stirring. Therefore, the ice level switch may be repeatedly closed and opened, so that the compressor is also repeatedly started and stopped in response to the above repeated operations of the ice level switch. Due to this repeated operations, the compressor is over-loaded and then a protector for the compressor may be operated, resulting in a shortening of the operating lifetimes of the compressor and the protector.
On the other hand, Japanese utility model Publication No. 59-38698 published on Oct. 27, 1984 of the same assignee as this patent application discloses the use of a thermal timer for the same control of such an auger motor and a compressor. This thermal timer has a drawback that a large variation of a delay time is produced depending on an ambient temperature and that a predetermined time delay may not be obtained due to the use of two thermal timers.